Good Carbs vs. Bad Carbs

Viewing carbohydrates as “good vs. bad” or “unhealthy” can confuse consumers, given that carbs are one of the three macronutrients we can’t live without. After all, they’re the body’s primary energy source. The problem is over-consuming carbs that are processed and stripped of their natural fiber, vitamins, and minerals.

But, according to Harvard School of Public Health, this view doesn’t address the effect of carbohydrates on blood sugar and chronic diseases. Enter the glycemic index (explained later). Taking this index into account, consider three perspectives on carbs:

1. Simple Carbs

These carbs are composed of one or two sugars (like fructose and glucose) with simple chemical structures that provide quick energy to the body.
• Processed: They are processed, refined, preserved, and flavored to make food more attractive, not more nutritious.
• Empty calories: If you don’t burn the excess empty calories, you can gain weight easily and risk hypertension, heart disease, stroke, and diabetes.
• Quick energy: They boost your energy then result in a “sugar crash,” leaving you tired, edgy, and craving even more carbs.
• Blood sugar: The faster rise in blood sugar and insulin can have negative health effects over time.

Simple-Carb Foods

White bread (the worst!)

Potatoes

Burger buns

Tortillas and wraps

Cookies and biscuits

White-flour pasta

Pizza dough

White rice

2. Complex Carbs

Complex-carb foods contain a complete source of carbohydrates, providing energy and nutrients.
• Natural sugars: Unrefined sugars from complex carbs are slowly absorbed by the body, preventing spikes in blood-sugar levels.
• Sustained energy: Complex carbs release energy slowly (low glycemic index) for sustained energy that doesn’t make you crash.
• Nutritious: They’re rich in vitamins and minerals.
• Fiber: Good for digestion, regularity, and controlling the appetite.
• Metabolism: Carbs are essential for optimum metabolism, while a low-carb diet can actually slow down metabolism, making it harder to lose weight.
• Sleep: The tryptophan in bananas, brown rice, pumpkin, oatmeal, and sweet potatoes helps you get a good night’s sleep!
• Brain and nervous system: Complex carbs are “brain food” for optimal brain and nervous system functions. You feel grounded, balanced, and less nervous or stressed. If low in carbs, you can feel light-headed, depressed, or unable to concentrate.

Complex-Carb Foods

Apples

Muesli

Barley

Oatmeal

Brown rice
Oranges

Carrots

Spinach

Lentils

Zucchini

3. Glycemic Index

Carbs are closely tied to blood-sugar levels. The glycemic index — Harvard’s preferred method for categorizing carbs — was developed to address this process and the interplay of insulin and glucagon that makes it possible. This is important because when the body can’t use insulin properly, it can lead to type 2 diabetes. The index ranks carbs by how quickly and how much they raise blood-sugar levels.
• High glycemic index: Foods like white bread that are rapidly digested and cause substantial blood-sugar fluctuations.
• Low glycemic index: Foods like whole oats that are digested more slowly, with a gradual rise in blood sugar.
• Glycemic load: Measures the digestible carbohydrate (minus fiber) a food actually delivers.